I have to agree with minicooper. On days when weather or some other factor is an issue, I gas up as much as I deem necessary - and in 90%, probably 99%, of such cases, the guys in Dispatch have beaten me to the punch and stuck the extra fuel on the flight plan already.
I've offloaded cargo on a few (admittedly rare) occasions, and never had to fight Load Control to get my way, because there was a good reason to be carrying the extra fuel and they could see it too.
The proposed re-clearance flights are NOT such flights, and on days when weather or traffic or any other factor become an issue, or if the stats for the flights in question change, I'd say the guys in Dispatch will have upped the fuel long before you get to the airport.
As I said in my earlier post(s), there should be no real reason for increased tension on the flight deck - you'll still divert with exactly the same fuel remaining as you would have done if you'd been carrying ten tonnes more. You'll just be doing so 'n' minutes earlier. And if you get to MITEX (or wherever) and find you don't have sufficient fuel to bypass your enroute alternate - (and that figure is clearly spelled out for you on the flight plan) - you land at Bahrain (or wherever) and stick whatever extra fuel you require on.